The beauty of finish sanding with a razor is the simplicity and speed. With one razor blade, I can quickly smooth a surface between coats on a job that would eat up several sheets of sandpaper.
Rusty metal is a very desirable finish in these days of worn, industrial, antique, distressed furniture. I have developed a technique for burning and finishing metal hardware to make it look very old.
I thought everyone made their own filler, especially when they ran out of filler from the store. Just take some wood dust, mix it with some sort of binder, and voilà, you have wood filler.